Lake Sakantsy more than 20 meters deep went under the ground in the Vladimir region of Russia, Ivan Shaposhnikov, the head of the department for water resources and management of the regional administration told Interfax on Wednesday.
According to the official, the forest lake disappeared due to the processes of karst formation (karstification) in the area.
"Underground cavities were created as a result of erosion, and the water in the lake, together with fish, drained into those cavities. We do not know what is going to happen to the lake in the future. Probably, the site will be filled with water again, and the lake will reappear. So far, though, there is just a sinkhole here," he said.
The forest lake was located near the Pivovarsky cavity, which is similar to the karst funnel formed in 1959. A karst funnel is a natural sinkhole. Such a sinkhole may appear when underground waters wash away the soil and rocks, and the soil subsequently collapses into the formed cavities.